It Was Wrong
by Sassy08
Summary: He knew that’s why she liked it, liked him. "Just admit it, Casey." "Admit what" “That you like me calling you sis,” One-Shot Dasey


Title- It Was Wrong

Summary:- He knew that's why she liked it, like him. "Just admit it Casey." "Admit what?" "That you like me calling you sis."

Disclaimer: I do not own Life With Derek.

Okay this is my first LWD fic, well actually it's my third, but it's my first one posted. The idea of Derek teasing Casey turned into this somehow and I just had to write it down. It didn't turn out the way I wanted though, but that could be because I'm sick and not really paying attention but... oh well. It was originally supposed to be much darker but I ran out of energy to do dark so you got this instead.

But anyways, if I get my energy back soon, I'll do an alternate version as a chapter two.

* * *

It was wrong.

He knew that's why she liked it, liked him. It was possible, but wrong; available but unattainable.

It was sin.

It was part of why he liked the games they played; the verbal fights that made them get up in each other's faces, the physical fights that allowed them to touch _every_ part of the other's body, those hateful looks that tried hid the lust behind their eyes.

No one would guess that the forbidden was Casey's deep dark fantasy. She wanted to be bad, to tease her step-brother, to be wild. But she wouldn't do it on her own. He knew he'd have to push her there.

And he knew just what to do and say to give her that push.

He waited until the house was empty and she came back from a date. He heard her walk through the front door and he got up to wait by his door for her to pass. He heard her come up the stairs and he leaned against the door frame.

"Hey sis." He greeted casually with a smirk.

"_Step_-sis." She corrected before rolling her eyes and ignoring him.

"Too long." He shrugged, following her into her room before she could shut the door. "Sis is easier and quicker to say."

"What do you want?" She was obviously irritated as she watched him lean against her door frame.

"Aww, did the date not go so well?" He teased. "You are home pretty early. He find someone better to be with?" She removed her jacket and placed it onto her bed. He took the time to let his eyes travel all the way down her body to the mini-skirt then back up to the low cut tank top that revealed more than enough cleavage to make him lick his lips.

"I actually ended it early." She said in her matter-of-fact tone of voice. "The guy was a pig." Derek's smirk reappeared on his lips as he walked up in front of her.

"Maybe you shouldn't be wearing these clothes then," He moved his left hand to let his fingers gently trace the arm hole of the shirt up to her shoulder where he left it. "Sis." He finished in a deep, low, drawn out way. He didn't miss the way her skin started to burn or the way her neck stiffened slightly.

"I can wear whatever I want." She countered, shaking his hand off of her shoulder.

"Not if you expect a guy to act nicely." He chuckled and leaned forward slightly. "If a guy sees you in something like that," His eyes raked over her one more time, spending a few extra moments on her chest. "They might think you were trying to _entice_ them." She pushed him away with minimal force and shook her head as he chuckled again.

"Well, I wasn't trying to entice him." She defended herself as she tried to usher him out of her room.

"Oh I know." His trademark evil smirk stayed on his lips as he turned around and walked out the door. "Night, _sis_." He called before closing the door behind him.

* * *

He waited patiently that night until everyone got home and went to bed. He only gave her the normal looks with an added smirk and the normal brushes against her skin when he passed her in the hallways. 

He set it up perfectly. He had emptied out the rest of the favorite shampoo in the sink and screwed up the order of the rest of the toiletries. She hated when things weren't in order and he knew she'd come into his room to yell.

And she did.

"De-_re_k!" She shouted as she barged into his room, where he laid on his bed, simply waiting.

"Yes dear sister?" He smirked yet again and sat up, noticing she was changed into her pajamas.

"Why do you _have_ to screw up _everything_ in my life?" She continued to yell. Without an answer, he stood up from his bed and went to shut his door. She got a somewhat confused look on her face.

"You should keep it down. Wouldn't want to wake the whole house with your screaming." He let the suggestive meaning in his voice come through to an obvious extent.

"Okay," She shook her head acting disgusted. But Derek knew that it made her stomach flip at the idea. "That's wrong on so many levels."

"Oh but that's what makes it _enticing_." She stopped for a moment and looked at him. The lust shown through the smirk and his eyes, his voice kept teasing her, and he was making her nervous. It excited her, but frightened her.

"What's wrong with you?" She questioned, taking a step backwards. He raised his eyebrows and chuckled deeply.

"Just admit it, Casey." He shook his head and took an advancing step to her.

"Admit what?" Her voice started to shake slightly and she took another step backwards.

"That you like me calling you _sis_," He always put emphasis on the word. "That you wear those types of clothes to entice _me_, your _step-brother_," She took another step back but found the back of her knees hitting the edge of his bed. "That you like the forbidden, wild side that we could have." He took a few more steps so he was only inches away from her body.

"Derek," She was unsure of herself and side-stepped him. "I do not. That's wrong." She slowly moved around him towards his door.

As she moved closer to it, his eyes followed her. He realized he was probably scaring her a little. He was probably coming on a little too strong, so it took it down a notch to a more "Casey-acceptable" level. So when her hand was placed on the door knob, he rushed over and gently put his hand over hers before she could turn it.

"Casey," He whispered into her ear as he moved behind her to mold her back to his front. His other hand came around and wrapped around her waist. "You know you don't want to go." He whispered as lovingly as he could into her ear, letting his lips brush across her skin. He could feel her suppress a shiver as her hand loosened on the knob, but didn't let go.

"Let go of me, Derek." Her voice came out as a whisper and couldn't sound less convincing if she had tried.

"Tell me you feel nothing and I'll let go." She sucked in a breath as he gently bit her earlobe. "Tell me this doesn't excite you." He started tracing small circles on her side where his arm holding her rested. "Tell me that knowing you're my sister and I'm offering something to you doesn't make you dizzy." He felt her hand loosen more so it was now just resting on the door knob.

"_Step_-sister." She corrected on reflex. He took her hand off the door knob.

"Which is what makes it okay." He let her hand fall to her side and he ran his hand up and down it. "If we were truly related, you'd have an issue with it. But because we're not, and it's still so very _wrong_, you like it." She didn't even try to stop the shiver this time. The chuckle she felt hit her neck made her do it again. "You like the wrong side, the sneaking out with me to parties, the sexual tension you know you shouldn't feel." All of a sudden, she turned around in his arms to face him. He leaned back just slightly, surprised by her action.

"But I hate the aftermath." She told him, leaning back against the door.

"Who said anything about aftermath?" He tilted his head and let the smirk return. He could tell she wasn't sure if that was a good or bad thing. "Look Case, I'm just bringing up what we both know." He pulled her flush against him, making her gasp. "We both know you like the dangerous, forbidden side of this along with the possibility of it being real. Give me fifteen minutes and if then you really want to leave, do it. Go run and tell your mom about what I tried to do to you." The idea brought fear to Casey's eyes. "Fifteen minutes, Case."

She licked her lips while contemplating the offer. She couldn't help the short nod that came before she was done thinking things over. The lust and evil returned in his eyes as he broke away from her, grabbing her hand. He led her over to his bed and had her sit down on it, legs off of the edge, facing him.

He bumped one of his knees inbetween her legs to spread them just slightly as he leaned down over her. He pressed his lips to hers biting her lower lip almost immediately, not willing to go slow. He could feel her lips start to respond to hers with just as much passion as he had. He licked her lips, not so much asking for entrance as he was demanding it in his own way. She complied and let him take full control of the kiss, letting him explore her.

He pushed her down on the bed, only allowing her to crawl up enough to be comfortable for her before he pushed himself against her, stopping her from moving. He removed his lips from hers and brought them down to her collar bone. Her skin burned her lips as he moved them.

"You like that, sis?" He teased. Her only reply was a low, strangled moan. He laughed softly. "I'll take that as a yes." He continued to kiss her collar bone before he used one hand to unbutton the first few buttons of her pajama top. "Do you like knowing your step-brother is above you?" His lips followed his fingers, kissing each bit of skin exposed.

"Derek," She moaned and shivered, bringing her hand into his hair. At that moment, he knew he didn't need fifteen minutes. She wasn't leaving.

"Yes, dear _sister_?" He stopped kissing and looked up at her. He felt her pull at the back of his head to bring his lips back up to hers. He stopped, inches from kissing her again and she let out a frustrated groan. "Shh now. Wouldn't want to wake up the house, would we?" He smirked before leaning down to kiss her again.

* * *

"Hey sis." He smirked as she passed him in the hall. 

"Don't call me that." She told him firmly as she walked by him, into her room. He let out a small laugh because he knew that she'd be in his room again tonight, wanting him to call her that, just like she'd been doing for the past two weeks. He knew she liked it.

It was wrong.

It's why she liked it.

* * *

Remember, reviews don't take long and we all love them. I even take flames, don't exactly love those but I'll take 'em!


End file.
